Source: Knicks targeting Sean Williams

A source familiar with the Knicks' free-agency plans told ESPNNewYork.com that the team is considering signing forward-center Sean Williams, who was waived by the Rockets this week.

There has been some speculation that the Knicks are interested in unrestricted free agent Josh Howard, but according to the source, they are not into him. Instead, the team wants to add a big man -- likely to serve as a backup to Amare Stoudemire on the depth chart. Currently, they don't have one.

There are more attractive bigs on the market, like Kenyon Martin, Andray Blatche, Louis Amundson, Chris Andersen and D.J. White. But those players have been looking for more than the veteran's minimum, which is all the Knicks can offer.

Williams, on the other hand, is in the Knicks' price range. The former New Jersey Net, whose career averages are 4.2 points and 3.4 rebounds per game in four NBA seasons, made less than $1 million in 2011-12 with the Mavericks and Celtics. While the former 2007 first-round draft pick out of Boston College hasn't made his mark yet in the league, Celtics coach Doc Rivers was impressed with his development last season. And that was on defense, which is Mike Woodson's mantra.

"He has a chance to be a shut-down defender, a shot-blocker, a guy that you can bring in and change the tempo of the game," Rivers said in July. "He rebounds the ball. He has that skill set in him. He has to marry himself to that."

While the Knicks technically have 15 players on their roster, Chris Smith, J.R. Smith's younger brother, is only under contract through the preseason. Williams, who's also reportedly on the Heat's radar, could be the team's final signing. Regardless, the Knicks can bring him to training camp (which starts Sept. 29) because the NBA has no limit on invites.

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